Thermographic phospors in the gas phase

气相热成像磷

• 批准号: 250934376
• 负责人: Professorin Dr. Barbara Albert
• 金额: --
• 依托单位: Rektorat
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2014
• 资助国家: 德国
• 起止时间: 2013-12-31 至 2020-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/250934376?language=en
• 关键词: Thermographic; phospors; gas; phase

Combustion processes that are turbulent will remain the base technology of technical energy conversion. A detailed knowledge of chemical, physical and coupled processes is required increasingly for the technologies of combustion. In particular it is important to understand the fields of flow and temperature. Simultaneous measurements of temperature and speed allow it to correlate both parameters. This is needed for the quantification of scalar fluxes and those are of eminent importance for the closing of the conservation equation that is used for the simulation.New developments towards a robust and quantitative temperature measurement are based on thermographic phosphors (TGP). TGPs are doped inorganic, crystalline solids with spectral properties that depend on temperature. The spectral and temporal emission changes with temperature and this is used for sensory purposes. Dopants are transition metals or rare earth elements. The use of TGPs for temperature measurements of the walls has been very successful. Adding TGP powders (particle diameter approx. 2 µm) to a fluid (gas or liquid) allows it to determine the temperature and the flow using particle image velocimetry (PIV). This is done by cross-correlation calculations of two Mie scattering images recorded consecutively. This method is of high potential for combined measurements of temperature and speed. From earlier studies it is concluded that the combination of PIV and TGPs will be very useful for measurements of scalar fluxes in hot gas applications and combustion environments under the following requirements: The precision for single shot measurements has to be increased and the signal-to-noise ratio above 1000 K has to be enhanced. The method is not yet used in combustion processes because there is a conflict of goals between the optimization of thermal and fluid dynamics and an enhancement of the signal-to-noise ratio.To overcome these limitations we will approach the goal of this research project on two tracks: 1) The TGPs will be optimized concerning quantum efficiency and cross section; 2) Hollow particles will be synthesized and tested for the application described above. Since it is very important that the particles fulfil the specifications dictated by the application it is mandatory that those who apply the particles to the combustion process collaborate closely with the experts that synthesize the TGPs. Both applicants of this proposal have shown in the past that their collaboration is very successful.

动荡的燃烧过程将仍然是技术能源转化的基础技术。对于组成技术，需要越来越多地了解化学，物理和耦合过程的详细知识。特别是了解流动和温度的场很重要。同时测量温度和速度使其可以将两个参数相关联。这是定量标量通量所需的，对于用于仿真的保护方程的关闭至关重要。对稳健和定量温度测量的新开发是基于热磷光器（TGP）。 TGP是无机掺杂的晶体固体，其光谱特性取决于温度。光谱和临时排放随温度而变化，这用于感觉目的。掺杂剂是过渡金属或稀土元素。使用TGP进行壁的温度测量非常成功。将TGP粉末（颗粒直径约2 µm）添加到流体（气或液体）中，可以使用粒子图像速度法（PIV）确定温度和流动。这是通过连续记录的两个MIE散射图像的互相关计算来完成的。这种方法具有高度测量温度和速度的高潜力。从较早的研究得出的结论是，在以下要求下，PIV和TGP的组合对于在热气应用和组合环境中测量标量通量非常有用：必须提高单射击测量的精度，并且必须增强1000 K以上的信噪比。该方法尚未用于组合过程中，因为在热和流体动力学的优化和信噪比的增强之间存在目标冲突。要克服这些限制，我们将在两个轨道上实现该研究项目的目标：1）TGP将优化量子效率和横截面； 2）将对上述应用进行合成并测试空心颗粒。由于粒子符合应用程序决定的规格非常重要，因此必须将粒子应用于组合过程的人与合成TGP的专家紧密合作。该提案的两个申请人过去都表明他们的协作非常成功。